Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland
The Vaigat strait ( Sullorsuaq ) in central West Greenland is well known for its susceptibility to landslides and historical landslide-generated tsunamis. Recent mapping of the seabed in the Vaigat Strait has revealed several prehistoric giga-scale tsunamigenic landslides; however, their ages are un...
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ftcopernicus:oai:publications.copernicus.org:nhessd109828 2023-05-15T16:28:14+02:00 Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland Korsgaard, Niels J. Svennevig, Kristian Søndergaard, Anne S. Luetzenburg, Gregor Oksman, Mimmi Larsen, Nicolaj K. 2023-03-13 application/pdf https://doi.org/10.5194/nhess-2023-32 https://nhess.copernicus.org/preprints/nhess-2023-32/ eng eng doi:10.5194/nhess-2023-32 https://nhess.copernicus.org/preprints/nhess-2023-32/ eISSN: 1684-9981 Text 2023 ftcopernicus https://doi.org/10.5194/nhess-2023-32 2023-03-20T17:23:12Z The Vaigat strait ( Sullorsuaq ) in central West Greenland is well known for its susceptibility to landslides and historical landslide-generated tsunamis. Recent mapping of the seabed in the Vaigat Strait has revealed several prehistoric giga-scale tsunamigenic landslides; however, their ages are unknown. Here, we report sedimentological evidence from six coastal lakes at 19 to 134 m above sea level (a.s.l.) on the Saqqaq foreland located at the eastern end of Vaigat. Using optical, X-ray fluorescence (XRF), and magnetic susceptibility core scanning in our sedimentological analysis along with a screening for marine diatoms and radiocarbon dating, we find evidence of at least two tsunami events occurring at 7.6 and 7.3 cal. ka BP. Using a previously published, recalibrated relative sea level curve from Arveprinsen Ejland ( Alluttoq ), located 40 km southeast of Saqqaq, we infer wave run-up heights of 41–66 and 45–70 m respectively for the two tsunamis. These run-up heights from prehistoric tsunamis are several orders of magnitude larger than the historic landslide-tsunami run-up heights at Saqqaq which only reached an elevation of c. 3 m in November 2000. While two giant tsunamis can be found in the lake sediment records, landforms from at least nine giga-scale landslides are present on the seafloor of Vaigat, we infer that the older giant tsunamis must have happened between the last deglaciation and the oldest sediment in the lakes (c. 10 to 8.5 cal. ka BP). Text Greenland Saqqaq Copernicus Publications: E-Journals Greenland Vaigat ENVELOPE(-52.947,-52.947,70.200,70.200) Arveprinsen Ejland ENVELOPE(-51.167,-51.167,69.717,69.717) |
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Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The Vaigat strait ( Sullorsuaq ) in central West Greenland is well known for its susceptibility to landslides and historical landslide-generated tsunamis. Recent mapping of the seabed in the Vaigat Strait has revealed several prehistoric giga-scale tsunamigenic landslides; however, their ages are unknown. Here, we report sedimentological evidence from six coastal lakes at 19 to 134 m above sea level (a.s.l.) on the Saqqaq foreland located at the eastern end of Vaigat. Using optical, X-ray fluorescence (XRF), and magnetic susceptibility core scanning in our sedimentological analysis along with a screening for marine diatoms and radiocarbon dating, we find evidence of at least two tsunami events occurring at 7.6 and 7.3 cal. ka BP. Using a previously published, recalibrated relative sea level curve from Arveprinsen Ejland ( Alluttoq ), located 40 km southeast of Saqqaq, we infer wave run-up heights of 41–66 and 45–70 m respectively for the two tsunamis. These run-up heights from prehistoric tsunamis are several orders of magnitude larger than the historic landslide-tsunami run-up heights at Saqqaq which only reached an elevation of c. 3 m in November 2000. While two giant tsunamis can be found in the lake sediment records, landforms from at least nine giga-scale landslides are present on the seafloor of Vaigat, we infer that the older giant tsunamis must have happened between the last deglaciation and the oldest sediment in the lakes (c. 10 to 8.5 cal. ka BP). |
format |
Text |
author |
Korsgaard, Niels J. Svennevig, Kristian Søndergaard, Anne S. Luetzenburg, Gregor Oksman, Mimmi Larsen, Nicolaj K. |
spellingShingle |
Korsgaard, Niels J. Svennevig, Kristian Søndergaard, Anne S. Luetzenburg, Gregor Oksman, Mimmi Larsen, Nicolaj K. Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland |
author_facet |
Korsgaard, Niels J. Svennevig, Kristian Søndergaard, Anne S. Luetzenburg, Gregor Oksman, Mimmi Larsen, Nicolaj K. |
author_sort |
Korsgaard, Niels J. |
title |
Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland |
title_short |
Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland |
title_full |
Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland |
title_fullStr |
Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland |
title_full_unstemmed |
Giant mid-Holocene landslide-generated tsunamis recorded in lake sediments from Saqqaq, West Greenland |
title_sort |
giant mid-holocene landslide-generated tsunamis recorded in lake sediments from saqqaq, west greenland |
publishDate |
2023 |
url |
https://doi.org/10.5194/nhess-2023-32 https://nhess.copernicus.org/preprints/nhess-2023-32/ |
long_lat |
ENVELOPE(-52.947,-52.947,70.200,70.200) ENVELOPE(-51.167,-51.167,69.717,69.717) |
geographic |
Greenland Vaigat Arveprinsen Ejland |
geographic_facet |
Greenland Vaigat Arveprinsen Ejland |
genre |
Greenland Saqqaq |
genre_facet |
Greenland Saqqaq |
op_source |
eISSN: 1684-9981 |
op_relation |
doi:10.5194/nhess-2023-32 https://nhess.copernicus.org/preprints/nhess-2023-32/ |
op_doi |
https://doi.org/10.5194/nhess-2023-32 |
_version_ |
1766017867113824256 |